What are you even asking? If you should get a 11-13 5.0 or a 96 cobra? or should you supercharge or turbo whatever you have? Either way Im sure the general consensus will be:
1. The 11-13 5.0 is a superior car although your really looking at 2 completely different classes/ price ranges of cars here so its really not fair to compare the two.
2. Modifying a vehicle regardless of if your building the engine, adding a supercharger, or a turbo will NEVER be an investment. When you go to sell you will likely get a fraction of what you invest back out of the car. This applies to any type of car and is not Mustang specific.
Well yea witch is worth buying and building Cuz the 5.0 I can get for like 19,000 from a dealer and the svt I can get for like 6k with like 60 k miles and witch would you recommend I buy and build I like both that's why I'm saying
Yeah, but what do you want the car for (nice DD, full race car, something in between?), can you define what a build is to you? They are both 'worth' buying given the price points but comparing a 5 k car to a 20 k car is comparing apples to oranges. Of course the 20 k car will be better. If you want honest constructive input you need to give a lot more details on what your hoping to accomplish and total budget.
Although this goes out the window if you have unlimited budget but my general rule of thumb is newer cars are good for light modding but make great daily drivers where as if I were to build a car I would choose an older car. Not only is the car cheaper but generally parts are cheaper, larger pool of after market parts with good feedback of how the parts perform, and a higher probability of getting used parts at a steal.